Fluid-pressure cylinder and piston.



J. E. POWELL.

FLUID PRESSURE CYLINDER AND PISTON.

APPLICATION FILED DEO. 3, 1913.

Patented May 5, 1914.

II-IIII @19H/neme Ww aff@ To all who-mit may concern:

sTATns PATENT curro :ro'HNj E.. Rowena., or retransmis, amener-A.

Be it known that lfl', JOHN E. Pownnr., a citizen of thelUni/ted States,residing at' Augusta', in thefcou'nty of Richmond' and State ofGeorgiafhaveinvented new and useful Improvements in and' Pistons,A ofspecification.

. This inventionrelates to' improvementsl in; fluid pressure cylindersand' pistons for use in connection with any preferred type of apparatusoperated by air, steam or other' fluid pressure, the object of' theinvention,

being to provide a telesco-pic'construction of cylinder andj pistonwhich is adapted tov collapse in close compass and which is adapted tobeextended to secure a desired length of travel, suchv construction ofcylinder and piston being of value where the space isl limited atthe-starting point and where the use of; a collapsible fluid pressure-`,power device is a factor.

A further object of the invention is to provide a telesco-pic cylinderand piston which is simple, reliable and comparatively inexpensive ofconstruction, which is so constructed as to maintain the collapsiblesec-l tions in rigid alinement when extended, and which is adapted toeffectually cushion the inward movement of said collapsible sections.

The invention consists of the features of construction, combination andarrangement of parts herein fully described and claimed, reference beinghad to the accompanying drawing in which Figure '1 is a verticalsection' of my im proved telescopic cylinder and piston as it appearswhenthe piston isextended to the full extent.- AFig..2 is a similar viewof the cylinder and piston showing the parts in collapsed condition.Fig. 3 vis a detail view of the bottom cylinder head and cushioningelement. Fig. 4 is a det-ail section through one of the piston sections,showing the packing gasket. y

Referring to the drawing,

which the' following. is a 1 designates the cylinder,`z-which isprovided at its base` with a flange 2, to which is detachably secured abottom head 3 having a 'flange 4 abutting against the flange `2, bolts5v passing through said flanges and securing said bottom head inposition. The body of the bottom head is offset downwardly to ,provide acounter-sink or concavity 6 having a beveled marginal wall 7 said cavityreceiv.

Specication of etters Patent. applicati meaisecemeersy 1era; semina.804,479. f r

Fluid-Pressure Cylinders whereby the cus ton sections.

FLUID-.PRESSURECYLINDER ANDx PISTON.

PatentediMa'y 5f, 19142.

ying' a cushioning 'element 8, adapted to' sustain the impact of thedownward, closing or collapsing movements of thepiston sections. Thiscushion may' be made of rubber, or other suitable material, and isherein shown in the' form of a disk having. a beveled surface 9'contacting with the beveled wall 7,

undue enlargement of distention of i'oning element is prevented.

The piston comprises a head or inner member 10, to which is connected'Athe piston rod 11, and one or'n'iore outer hollowl or tu-v bularsections, two of which are shown in the' present instance anddesignated' 1'2 and 13, respectively. The upper end of the cylinder 1'and upper end of each of the piston sections 12 and 13' is provided withan'annular inturn abutment flange 14, while the lower end of each ofsaid cylinder sections 12 and13 1s provi'ded'with an outturned annularabutment' flange 15'. The piston 10 when moved upwardly is adapted toengage the. flange 14 of' the section 12, and the flanges 15 of thesection 12 is adapted to engage the flange 14 of the section 13, whilethe flange 15 of the section 13 is in turn 'adapted to engage'the flange14 of the cylinder 1, whereby the outward movements of the respectivesections of the pistons are limited and said sections adapted to' becoupled to leach other 'on' its outward movement to extend or raise thepiston to the limit ofits upward movement. The cylinder is provided withl a fluid pressure inlet 16 opening through its bottomhead, and inpractice suitable valve controlled supply and exhaust connections areemployedtoregulate the ilowy of fluid pressure to and from the cylinderland pis- These fluid supply and exhaust connections are not hereinshown, as they constitute no part of the present invention. When thepiston is collapsed, as shown in Fig. 2, the .sections telescope withinveach other and are inclosed wholly vwithin the cylinder l, and thelower abutment portions thereof contact withthe cushioning member 8,which sustains the downward impact as each cylinder section reaches thelimit of its downward travel, thusreducing all jars and concussions.cylinder and piston sections are of sulficient area to stay and rigidlysupport the piston sections and prevent Wabbhng. thereof when saidpiston sections are extended, as

will be readily understooid.

It will 'be apparent4 fromI the foregoing The abutment flanges of thethat the construction described insures a desirable long range of travelof the piston and flange 15 of each piston section 12 and 13 is providedwith suitable packing, preferably comprising a leather packing ring 17clamped and held against its bottom face by a clamping ring 18 securedto the piston member by screws 19. The louter eripheral edge of the ring18 lies Some distance inwardly of the periphery of the portion of thepiston member to which it is attached and the free edge 20 of the gasketor packing ring 17 projects beyond and is adapted to fold back over theperiphery of said packing ring to contact with the wall of the cylinderor cooperating piston section and effect a fluid tight joint. Theportion 20 of the packing ring is adapted to be held pressed against thesurface against which it is designed to bear or by means of a spring 21seated within a groove 2Q in the periphery of the ring 18. Vent openings23 are provided in the cylinder and each of the intermediate pistonsections for the purpose of permitting of the exhaust of any airconfined between the-engaging portions of the cylinder and pistons whenthe piston is raised, which ports are closed against the ingress of airwhen the piston is extended, but`permit of the entrance of air when thepiston collapses to avoid the formation of i a partial vacuum.

Frein the foregoing description, taken in connection with the drawings,the construction and operation of my improved cylinder and telescopicpiston will be readily understood, and it will be' seen that theinvention provides a device of this character which isv simple, reliableand inexpensive of construction, and which at the same time is desi edto secure an easy and stable motion o the parts while cushioningallshocks and jars, the advantages of which will be apparent.

I claim 1. A fluid pressure power device comprising a cylinder, and apiston comprising a plurality of telescopic sections, adapted to beextended beyond and to collapse within said cylinder, said cylinder andpiston sections being provided with means for limiting the outwardmovements of said Ipiston sections, and means for cushioning the inwardmovements of said piston sections.

2. A fluid pressure power device comprising a cylinder, and a pistoncomprising a plurality of telescopic sections adapted to be extendedbeyond and to collapse within said cylinder, said cylinder and pistonsections being provided with abutment surfaces to limit the outwardvmovements of said piston sections and with air exhaust passagescoacting with said surfaces, and means for cushioning the inwardmovements of said piston sections.

3. A fluid pressure power device compris ing a cylinder having a bottomhead provided with a concavity therein, a piston composed of a pluralityof telescopic sections, said cylinder and piston being provided withcoperating abutments to limit the outward movements of said pistonsections'and coacting air release ports controlled by said abutments,packing rings on the abutments of the piston sections, saidpistonsections beingl adapted to be extended from and to collapse withinthe cylinder, and a cushioning element seated in the concavit of thebottom head of the cylinder to cus ion the closing movements of saidpiston sections,

In testimony whereof I affix my signature in presence of two witnesses.

JOHN E. POWELL.

Witnesses:

ST. ELMo CRocKER, CHAs. GUTHRIE.

